NOVEMBER,1900 MONTHLY WEATHER REVIEW. 487

~ Clayton found on the day that the kite observations were made regard to rainfall. We make four divisions as follows, viz : on which he based his calculation, that the observed rate o 1. The north end.-This includes all that portion of the precipitation was only one-tenth of the computed rate. HI island to the north of a line drawn, say, from Sandy Point concluded that much of the condensed moisture was reah (S. Pt.) in a nearly northeasterly direction, crossing the foot sorbed by the unsaturated lower layers of the atmosphere. hills of the mountains and then to the sea. Roughly speak- While this might be true with a saturation temperature o ing, this embraces about twenty-eight per cent of the culti- 34.8O F., such as he observed, since the total amount of vapo vated portion of the island. The rainfall in this district is, present in the air would necessarily be small, as shown b; perhaps, the least influenced by the elevated portions of the Table 3, we can not suppose that any such proportion of thl island, or if at all, certainly very differently affected thereby. moisture condensed under conditions such as we have hen The average annual rainfall on this area, as determined by considered would be so reabsorbed. the records of the thirteen stations covering a number of Undoubtedly there are many considerations that will con years, is 68.51 inches, as indicated on the map, and also in tribute to reduce the precipitation to a rate much below tha Table 1. The greatest annual rainfall on record, 114.68 of condeneation. Nevertheless, Professor Bigelow's tables fo inches, occurred at Brotherson's estate, within this division, computing the adiabatic changes under various surface con in 1S98. ditions have opened up to us a profitable field for study. 2. The enst side.-This division embraces all the estates on the windward side of the island, and represents about twenty- RAINFALL ON THE ISLAND OF ST. KITTS, W. I. seven per cent of all the cultivated portion of the island. By W. H. ALEXANDER,Observer, Weather Bureau, dated Nov. 19, 1900. The influence of the mountains npon the rainfall of this This paper is the fulfilment of a purpose expressed in ai district is atteeted by a marked decrease of more than 13 article on the Climatology of St. Kitts, published in t,hc inches in the yearly average from that of the north end, REVIEW,Annual Summary, for 1899, and for o1,vious reason1 being only 55.2s inches. This decrease may be partly ac- the two should be considered together, the one being supple counted for by a phenomenon frequently noticed, especially mentary to the other. on days when strong convectional currents are present-the passing of the clouds around instead of over the mountains. 1 For instance, n large cumulo-nimbus cloud may be seen ap- proaching from the east, but as it nears the land it will be seeu to change its course and pass either around the moun- tains or perhaps will be drawn over the depression in the niountain range of the main body of the island. As a result, we find a very heavy rainfall on both sides of this depression, 5s shown by the records of the two estates, Molyneux and Wingfield, given in the talde. The clonds sometimes divide, me portion going north or south of the mountains, and the 3ther over the depression just mentioned. 3. The soictk end.-This division includes the picturesque and fertile Valley of Basseterre, and is encircled on three 3ides by hills and mountains of heights varying from 400 to 1,300 feet, as shown on the map ; it contains about twenty- nine per cent of the cultivated land of the island, and has 'i* 4 SP $?y.." the smallest average rainfall of the four districts, it being mly 53.12 inches, or more than two inches below the east ~ .,&&,.:"% 91y::t;r 3ide and 15 inches below the north end. 4. The west sit1r.-This division contains only about 16 per :eut of the cnltivated lands of the island and is situated on the leeward side of the great mountain range, which runs ridge-pole like through the central part of the main body of ,he island. The average for this district-66.10 inches-is Jot far below that of the north end. Perhaps the most in- ;eresting point iu this district as regards our present discus- lion is that of the Wingfield estate mentioned above. Taking the island as a whole the records seem to indicate tu annual average of 59.25 inches, which is an appreciable ncrease upon the average given in the discussion in the An- iual Summary for 1899, naniely, 51.66 inches ; which, how- wer, was the average for Baseeterre alone. The greatest lownpour at any one time was that known as the flood of LS80, an account of which may be found 011 page 196 of the ~EVIEWfor January, 1899. In addition to what has been said will add a note found in Mr. Evelyn's old records made at ,he time of the food. It reads: Supposed that 36 inches fell during the time from 19 o'clock (noon) o 3 a. m. uf 12th. Town flooded ; immense damage to houses ; 230 ives lost and missiug. The month of March, 1891, is the driest month on record. rhe average for the island was only 0.16 inch, whereas the iormal amount for that month is about 1.5'1 inches. Atten- ,ion is called to the fact that there is a difference of only 0.08 nch in the annual mean at Molyneus and Wingfield estates.

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The former is on the windward side of the mountains about 700 TABLE3.-A compmalim atudy of ik rainfall on. four of ik Leeward feet above the sea and the latter ie on the leeward Bide about Islands for the year 1895. 176 feet above the sea. Then again the records of Upper and Lower are worthy of note. Here we have two estates similarly situated, except that one is about 400 feet higher than the other. As a result of this difference in elevation we see a marked and very uniform difference in the monthly and yearly means. See Table 2. Montserrat.. ... Antigua ...... In the year 1899 the prevailing wind for each month in the Nevis ...... 9t.Kitts ...... year was from the east except for December, which was north- I east. Or, to state it in another way, the wind was from the NOTE.-The number of stations on each island reporting is shown in first column. east during 54 per cent of the time and from the northeast TABLE4.-Resulla oj'8imultaneoue obrractwna at two statio118. during 32per cent of the time. The prevailing winds, together [The location of each etation is shown on the map, fig. 2.1 with such other facts as may be gained from this and preced- FOUNTAIN ESTATE, ST. KITTS. ing papers on this subject, prepare the reader for an intelli- [Elevation about 850 feet above sea level.] gent appreciation of the agencies which operate in producing -~~~ and modifying the rainfall on the Island of St. Kitts. I Temperature. Precipitation. The gages used at these stations were imported from Eng- land and appear to be well and scientifically constructed, there being a fixed and uniform ratio between the diameter of the funnel and the diameter of the graduated tube. The measurements are made with great care and regularity, the day, as a rule, is counted from 6 a. m. to 6 a. in., local time. It only remains to be said with reference to Table 4 that it is the result of an effort to secure eome mountain observa- tions and is almost self explanatory. Fountain estate is about 860 feet above sea level and the only available place ...... Ci.0' c8.P 85 1.24 &I 4.98 20 for much work. The owner, Miss Marshall, kindly consented May ...... 1 79.1. t1.2. 84 12 70 b 1.28 11 to do the work if provided with instruments. Accordingly WEATEER BUREAIT, ST. KITTB. she was equipped with maximum, minimum, and dry ther- [Elevation 29 feet above sea level.] mometers, and these were duly installed on February 14, ~~~ ~ ~~ ~~ 1900, and the first observations were made on the following February ...... 78.2 :3.? 80 March ...... 77.4 82.8 5 day. The observations were taken on seventy-fifth meridian April ...... ~ 78.2~ 73.01 time and were continued up to and including May 17, 1900. May ...... 80.8 76.1 , , I Only two observations were missed during the time. Unfor- &Oneobservation missing. tunately the maximum thermometer was broken at the end TABLE5.-Res idla of tii eteo?.obyical o bae r on lio ti 8. of thH first week, so that no note is made of the readings of the maximum thermometer except for the one week. The corre- a. c i Eg zi Thermometer. $r; sponding data on record at this oEce for precisely the same rd'3 time are also inserted in the table for the sake of comparison. Time. ilg !2g Remarks. The data in Table 6 are fully explained in the foot note, gz 4s Dry. Wet. ~~~~~ ~~______and it only remains to say that the work was done at my re- Feet. Inches. 0 0 quest aud by responsible parties. 8:30 a. m.. 1,oO 29.02 74.2 69.5 79 Open pasture; sun shining. 9:Wa. 111.. 1,500 28.52 68.0 67.0 95 Undera tree. cloudy. l.-Nonthly and yearly mean8 of rainfflll within each ihe four 9:30 a. IU.. 2,ooO 27.86 66.0 ...... In the forest! sun shining. TABLE of i0.W a. m.. 2,740 27.17 63.8 69.0 97 Lipof crater: owf forest; overcast. dimeion8 dnhwhich the ieiatad k divided. 11:OOa. m.. 2,i50 5.75 65.0 65.0 io0 Openland: bottomofcrater;ralned immediately after. 1:05 p. m.. 3,100 26.75 ...... Lip of crater under the peak. - - ~___

Northend .... 13 336 242 11 92 3.63 8.16 439 641 7.22 8.47 7.39 7.87 5.57 Fq.51 EastsldeSouthend ...... 115 12 "002.95 11:962.Z 'l:%1.12 13.122.08 16.455.53 13:403.08 ~5:Ol4.59 16.986.16 17.466.96 1.314.81 1.944.92 ((94.9CI53.12 155.28 West aide ...... 4 4.18 2.53 11.91 2.30 14.41 3.64 6.07 17.37 6.84 p.66 6.45 5 50 I6G.10 NOTES ON LOCAL WHIRLWINDS IN NEW BRUNSWICK. I/ I I I I l1--1 I Ill By SAMUELW. KAIN. VoTE.--Ttie 6rst column shows the number of stations upon whose recordaxe means are based. The province of New Brunswick is very rarely visited by TABLE2.-Monthly and annual mcane for certaiib eatalea which for local violent storms, and the undesirable phenomena due to atmos- eai~seapresent inleraating poirc la. pheric disturbances have been recorded only at long intervals. The tornadoes and cloudbursts which are reported so often from the west and south are happily almost unknown here. Still it must not be forgotten that we have had such storms. On August 17, 1895, a tornado of considerable violence swept over the parish of Dumfries, York County, and in the United 11 Brotherson's.. .I 5 4.33 8.69 2.58 '4.8 7.42 7.26 8.30 7.86 10.487.94 52 5.76 85.21 States WEATHERREVIEW for Rlarch, 1598, I have described a 3.31 2.29 2.10 lb.5' '*lr.12 5.AO 15.88 7.30 8.60,8.R 10.21 5.59 '1.@2 2.47 1.57 1.66 -.66 4 31 3 48 3.94 l5.76 5.964.91 5.05 3.04 45.01 cloudburst ohserved near Snsses on August 1, 1897. 3.04 1.93 1.94 2.92 Ii51 4 R7 6.24 6.W 5.65 5.81 3.59 58.33 It may therefore be of some interest to briefly describe a 5 41 4.85 3.79 3.75 4.99 5.15 5.8.1 8 00 7.438.30 d .09 7.14 71 51 Basceterre ... 3166 1.89 2.07 13.2 14.18 14.00 14146 15167 1 6.45i6.54 1 i.383.76 151:38 sinall whirlwind observed at 4 p. m. on the 24th of May, 1900, IIIII I I, I'll I1 hy Mr. Keith A. Barber. While Mr. Barber was standing by NOTE.-The number of years record involved is shown in first column. These estates are located on the accompanying map, fig. 8. the side of a pool of water about six miles from Clarendon

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